Extracellular vesicles (EVs) are membrane bound particles, with nanometer-range size (20-5000 nm) that are secreted by all cell types and play a key role in cell-to-cell communication. (1-4) EVs are extremely diverse in size and composition as they carry many bioactive compounds such as proteins, enzymes, lipids and nucleic acids. Factors such as cell growth, migration, apoptosis, disease or physiological stress can all influence the properties of secreted EVs. (5-7) Moreover, the EVs surface cargo signature will determine their fate after secretion, as it will influence their uptake and effect on the target cells. Indeed, EVs play an active role in the modulation of pathophysiological processes, like disease modulation and progression. (8) The most widespread techniques for characterizing extracellular vesicles are nanoparticle tracking analysis (NTA) for sizing, flow cytometry (FC) and fluorescence microscopy (FM) for cargo characterization, and electron microscopy (EM) for sizing and morphology. However, none of these techniques can output size, cargo composition and morphology in one high-throughput measurement.
